This invention relates to the field of oral surgery, and, more specifically, periodontal surgery. The invention provides a method and appliance for promoting the healing of oral tissues which have been damaged by disease.
Periodontal disease occurs when bacteria (plaque) multiply on the teeth and gums. If the bacteria are not removed, they eventually cause inflammation of the gums, and destroy the gum tissue. The condition becomes still worse when the bacterial infection approaches the underlying bone. In many cases, some of the bone will have been eaten away as a consequence of periodontal disease, before the patient seeks treatment.
The bone tissue which is lost to periodontal disease can be regenerated automatically by the body, with the passage of time. One can promote rapid regeneration of the bone tissue by isolating the bone from other tissues in its vicinity, and especially from the gum tissue overlying the bone. To provide such isolation, it has been known to use a physical barrier to separate the bone tissue from surrounding tissues. A barrier can also be used to promote regeneration of other oral tissues, such as the cementum, which is on the tooth, and the periodontal ligament, which joins the tooth (via the cementum) to the bone. Such a barrier allows the bone tissue, or other oral tissues, to regenerate itself without "competition" from other surrounding tissues, specifically gum tissue. In the absence of a barrier, surrounding tissues (such as gum tissue) would fill the empty space formerly occupied by the bone and periodontal ligament, and would tend to prevent the bone from fully restoring itself to its former condition. The barrier therefore provides means for favoring the regeneration of the damaged bone, cementum, and periodontal ligament over the growth of other oral tissues, specifically gum tissue.
One material which has been found useful in forming the above-described barrier is polytetrafluoroethylene (PTFE), also known by the trademark TEFLON. In particular, it has been known to use a periodontal barrier made of a specific form of TEFLON, sold by W. L. Gore & Associates, Inc. under the trademark GORE-TEX. GORE-TEX periodontal materials are commercially available, and are provided in the form of generally flat membranes having various sizes and shapes. These membranes have been widely used to promote regeneration of damaged oral tissues.
The major advantage of the GORE-TEX material, when used as the periodontal barrier described above, is that the material is biocompatible. That is, oral tissues (particularly gum tissue) will become attached to the GORE-TEX membrane, holding the membrane in place while the process of tissue regeneration proceeds. Regeneration of the supporting structures of a tooth, i.e. bone, cementum, and periodontal ligament, requires that the barrier membrane be kept in place for at least 4-6 weeks. However, the longer the barrier is allowed to remain in position, the more likely one is to obtain a more mature and stable regenerative result.
The GORE-TEX membrane has not been entirely successful as a periodontal barrier. Regardless of how tightly one tries to fasten the GORE-TEX membrane around the tooth, there always exists a space between the tooth and the membrane, and this space allows saliva and bacteria to percolate into the healing area. Exposure of the membrane promotes the growth of harmful bacteria, often necessitating the removal of the membrane before the healing process is complete. More importantly, when the membrane is prematurely removed, the newly-regenerated tissue is exposed. Because of its fragile nature, the new regenerated tissue can often be wiped away with a dental instrument, nullifying some of the effect of weeks of healing.
The present invention provides a periodontal barrier which promotes the healing of oral tissues, such as bone, cementum, and periodontal ligament, and which also overcomes the disadvantages discussed above.